I think you would have to help the most Conservative Republican to get through the primary. The Party will undermine that candidate to help the liberal.
Saw that firsthand with Lugar mourdock 2012 primary a number of lake co rinos supported Lugar and provided not only help for Donnelly in General but inside info from mourdock campAign. The reward for them was to keep sweet county board gigs and some local business. One is actually a candidate for strategy senate as a r running in a d district this season. Has been informed payback is a real b-—h
A good example of how to do it is Brad Wenstrup, a combat surgeon in Iraq and bright guy, upset Jean Schmidt in Ohio-2 district (Cincinnati and southwestern Ohio).
Brad is strictly Tea Party endorsed and votes the right way on veterans, guns, budget, foreign policy, pro-life, you name it.
http://en.wikipedia.org/wiki/Brad_Wenstrup
My point is, you have to become “The Party”.